Biographies of Women Mathematicians

Grace Murray Hopper

December 9, 1906 - January 1, 1992

Written by Rebecca Norman, Class of 2000 (Agnes Scott College)

Grace Brewster Murray Hopper was born in New York City on December 9,
1906, to
Walter Fletcher Murray and Mary Campbell Horne Murray. The oldest of three
children, she was
intensely curious at an early age. Even at age seven, she showed a
particular love for gadgets,
disassembling seven alarm clocks in the attempt to determine how they
worked. Hopper's
parents provided a strong foundation for her inquisitiveness. She shared
her love of math with
her mother, who studied geometry by special arrangement when serious study
of math was still
thought improper for a woman. Her father, a successful insurance broker
despite the double
amputation of his legs, encouraged all his children, through his speech
and example, that they
could do anything if they put their minds to it. He inspired Hopper to
pursue higher education
and to avoid being limited to typical feminine roles.

In 1923, at age 16, Hopper applied to Vassar College. However, she failed
a Latin exam
and Vassar told her she must wait a year. Undaunted, she became a boarding
student at Hartridge
school in New Jersey, entering Vassar the following year. She graduated
Phi Beta Kappa from
Vassar in 1928, with a Bachelor's Degree in Mathematics and Physics. In
1930, at age 23, she
received her Master's Degree in Mathematics from Yale University. The same
year, she married
Vincent Foster Hopper, an English instructor at New York School of
Commerce. A year later,
Vassar hired her as a mathematics instructor, for a salary of $800 per
year. Hopper taught at
Vassar from 1931 until 1943. During that time, she earned a Ph.D. from
Yale in 1934 (with a thesis on "New Types of Irreducibility Criteria"),
and was
promoted from instructor to associate professor. In 1936 she published
a paper on "The ungenerated seven as an index to Pythagorean number
theory" in the American Mathematical Monthly.

With the outbreak of World War II, Hopper made a life-altering decision to
serve her
country by joining the Navy. The process was not an easy one. At age 34,
weighing 105 pounds,
she was considered overage and underweight for military enlistment. In
addition, her position as
a mathematics professor was declared crucial to the war effort. Navy
officials asked her to
remain a civilian. These obstacles did not stop Grace Hopper. She obtained
a waiver for the
weight requirement, special government permission, and a leave of absence
from Vassar College.
In December 1943, she was sworn into the U.S. Naval Reserve. She went on
to train at
Midshipman's School for Women, graduating first in her class.

Hopper's first assignment was under Commander Howard Aiken at the Bureau
of
Ordinance Computation at Harvard University. There she became the third
programmer of the
Mark I, the world's first large-scale automatically sequenced digital
computer. The computer was
used to calculate aiming angles for Naval guns in varying weather
conditions. Because the
numbers were so pertinent, Hopper and her assistants were often required
to run and monitor the
system twenty-four hours a day. They spent countless hours transcribing
and inputting codes for
Mark I and its successors, Mark II and III. Hopper received the Naval
Ordnance Development
Award in 1946 for her work on the Mark series.

During her work with Mark II, Hopper was credited with coining the term
"bug" in
reference to a glitch in the machinery. This story is apparently a bit of
computer folk-lore, however, as the term had already been used by Harvard
personnel for several years to describe problems with their computers. It
is the case that she and her team of programmers did find a
moth which flew through an
open window and into one of Mark II's relays, temporarily shutting down
the system. The moth
was removed and pasted into a logbook [Photo
of that bug]. At that time the use of the word "bug" referred to problems
with the hardware. In the mid 1950's, Hopper extended the meaning of the term
"debug" to include removing
programming errors.

In 1946, at forty years of age, Hopper was told that she was too old to
remain in active
service. By that time, she
was divorced with no
children. Turning down a renewed position at Vassar, Hopper chose to
remain at Harvard as a
civilian research fellow in Engineering Sciences and Applied Physics until
1949. Then, Hopper
made a risky business move. She left Harvard to join Eckert-Mauchley
Computer Corporation as
a senior mathematician. The gamble paid off when the company introduced
the BINAC, Binary
Automatic Computer, which was programmed using C-10 code instead of the
punched cards
utilized by the Mark series. This paved the way for production of the
first commercial
computers, UNIVAC I and II. Although great improvement had been made,
programming the
BINAC still proved difficult. Hopper taught herself how to add, subtract,
multiply, and divide in
octal, a number system with base eight that uses digits 0 through 7, in
order to facilitate the
process. Unfortunately, her checkbook suffered, as she occasionally
subtracted an octal instead of
a decimal from her balance.

Hopper remained with the company when Remington Rand bought it in 1950,
and later
when it merged with Sperry Corporation. During this time, she developed
the first compiler, A-0,
which translated symbolic mathematical code into machine code. Using call
numbers, the
computer could retrieve subroutines stored on tape and then perform them.
The A-2 became the
first extensively used compiler, laying the foundations for programming
languages. In 1952, she
published her first paper on compilers. Hopper's next move was radical.
She suggested that
UNIVAC could be programmed to recognize English commands. Despite ridicule
from her
peers, Hopper succeeded in developing the B-0 compiler, later know as
FLOW-MATIC, which
could be used for typical business tasks such as payroll calculation and
automated billing. Using
FLOW-MATIC, she taught UNIVAC I and II to understand twenty English-like
statements by
the end of 1956.

It soon became apparent that a standardized, universal computer language
was necessary.
In 1959, the first specifications for the programming language COBOL
appeared. Members of
Hopper's staff helped to frame the basic language design using FLOW-MATIC
as their
foundation. Hopper then helped to create standard manuals and tools for
COBOL. In 1966,
Hopper's age forced her to retire from the Naval Reserves. However, in
less than seven months,
the Navy, unable to develop a working payroll plan after 823 attempts,
recalled Hopper from
retirement in order to help standardize the high-level Naval computer
languages. Her
reinstatement made her the first Naval Reserve woman to return to active
duty. Her original re-appointment was for six months, but it was
later extended indefinitely.
During her remaining
years with the Navy, Hopper aided in the production of a generally
accessible COBOL certifier
as well as translator programs to convert non-standard COBOL languages
into the standardized
version.

In 1983, by special Presidential appointment, Hopper was promoted to the
rank of
Commodore. Two years later, she became one of the first women to be
elevated to the rank of
Rear Admiral. In 1986, after forty-three years of service, RADM Grace
Hopper ceremoniously
retired on the deck of the USS Constitution. At eighty years, she was the
oldest active duty
officer at that time. She spent the remainder of her life as a senior
consultant to Digital
Equipment Corporation.

Hopper received numerous honors over the course of her lifetime. In 1969,
the Data
Processing Management Association awarded her the first Computer Science
Man-of-the-Year
Award. She became the first person from the United States and the first
woman to be made a
Distinguished Fellow of the British Computer Society in 1973. She also
received multiple
honorary doctorates from universities across the nation. The Navy
christened a ship in her honor.
In
September, 1991, she was awarded the National Medal of Technology, the
nation's highest honor in engineering and technology.
However, over all these distinctions, Hopper claimed her work as a teacher
as
her most important and rewarding accomplishment.

Admiral Hopper's perseverance and unconventional style led her to great
achievements in
all her professional endeavors. Never forgetting her father's example, she
took on the established
system and won. A true pioneer, she helped to pave the way for modern
computing, as well as
professional women everywhere. Hopper truly lived up to her motto "Dare
and Do."

Rear Admiral Grace Brewster Murray Hopper died January 1, 1992. She was
buried with
full military honors at Arlington National Cemetery.